Small-animal mount assembly

ABSTRACT

The small-animal mount assembly of the present invention can include a table member suitable for mounting a small animal. The table member can be selectively positionable into a desired table plane and can include at least one ECG pad and/or at least one grid of electronic heating elements disposed onto a top surface of the table pad. The assembly can also include a control apparatus electrically coupled to the at least one ECG pad and/or the at least one grid of electronic heating elements.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to and the benefit of U.S.Provisional Application No. 60/417,167, entitled “GUIDED INJECTED RAILSYSTEM,” (attorney docket No. 00518-0008), filed on Oct. 10, 2002; U.S.Provisional Application No. 60/468,959, entitled “GUIDED INJECTION RAILSYSTEM,” (attorney docket No. T00518-0008-USP2), filed on May 9, 2003;U.S. Provisional Application No. 60/417,185, entitled “SMALL ANIMALSURGICAL INTERVENTION PLATFORMS,”(attorney docket No. T00518-0009),filed on Oct. 10, 2002; and U.S. Provisional Application No. 60/468,960,entitled “SMALL ANIMAL SURGICAL INTERVENTION APPARATUS,” (attorneydocket No. T00518-0009-USP2), filed on May 9, 2003, all of which areincorporated in their entirety in this document by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a small-animal imaging system,and more particularly to a multi-rail imaging system for maintaining adesired image plane during an imaging session.

[0004] 2. Description of the Prior Art

[0005] Over the past few years researchers in disciplines as diverse asneuroscience, developmental biology, genetics, and oncology havestruggled with the challenge of injecting microliter and nanoliterquantities of fluid into discrete regions of organ systems. With thedevelopment and launch of ultrasound biomicroscopy (UBM) technology inthe small animal imaging marketplace, the capacity to non-invasivelyobserve, in real-time, the position of a needle or probe relative to anorgan became a reality. One disadvantage with present positioningsystems for animals is that straightforward repeatability of positionwith different animals is not possible.

[0006] For example, during injections procedures, a common problem hasbeen the challenge of aligning a needle guidance device, which injectsvery small quantities of fluid, with a UBM scanhead device.Micromanipulation of both devices is necessary to help ensure that theinjector needle of the needle guidance device lies within the same planeas the ultrasound scanhead so that the operator can guide the needle tothe organ of interest. Consequently, this is a laborious andtime-consuming process, which is aggravated by the need to move bothdevices away from an animal handling device, upon which a small animalis mounted, when a different animal is to be scanned. Current systemsuse independent, non-integrated, positioning methods for the variousdevices used in the imaging session.

[0007] Much information and expertise is available on the sequence andthe manipulation of the mouse genome. Because of the similarity betweenthe mouse and human genomes, the mouse is used as a model forunderstanding human gene function, and a model for many human diseaseprocesses. Manipulations permitted by guided injection techniquefacilitate experiments to further the understanding of genome function,the functional stages of organ development, the differentiation of stemcells, and facilitate testing of new interventions for models of humandisease. Ultrasound imaging can be used to generate a high resolution,cross sectional image in real-time so the imaging system can be operatedwhile a needle is introduced into the small animal that gives theoperator immediate accurate feedback for positioning of the needle tipin the target space. However, there is a need for providing a system toprovide for quick manipulation of imaging apparatus and, if used,injection apparatus, around a sequence of different animals in a timeefficient manner.

[0008] There is a further need for a mounting table for handling ofsmall animals, such as mice, rats, rabbits, and the like, in both aminimally stressful and time efficient manner during the course of animaging session. Control of the animal's physiological condition is ofparamount concern, but doing so in an environment that permits themovement of the immobilized subject in a variety of positions tomaximize the success of placing the animal within the imaging plane ofthe imaging apparatus. Further complicating these procedures is the factthat some protocols necessitate that the embryos of pregnant animals beexternalized from the abdomen to provide for improved imagingresolution.

[0009] To date, no device serves each of the needs outlined to enablethe safe and effective delivery of anaesthesia to small animals, thephysiological monitoring of the immobilized subject, the capacity for arange of motion, and the ability to successfully externalize embryos ona specialized table.

SUMMARY

[0010] The small-animal mount assembly of the present invention issuitable for mounting a small animal thereon for desired medical andimaging procedures. In one example, the small-animal mount assembly hasa control apparatus, a table member, and at least one ECG control pad toaid in monitoring the health status of the secured small animal. Thetable member has a top surface and defines a table plane. In oneexample, the table member can be selectively oriented so that the tableplane of the table member can be positioned in a desired table plane.

[0011] The at least one ECG control pad is operatively attached to thetop surface of the table member and is electrically coupled to thecontrol apparatus. Each ECG pad generates an ECG signal representativeof a sensed ECG of a portion of the small animal that is disposedthereon the ECG pad.

[0012] For comfort of the small animal, the small-animal mount assemblycan also include at least one grid of electronic heating elementsdisposed onto the top surface of the table member. The at least one gridof electronic heating elements can be coupled to the control apparatusand aid in maintaining the top surface of the table member at a desiredtemperature. The small-animal mount assembly can also include athermocouple connected to the top surface of the table member andelectrically coupled to the control apparatus. The thermocouplegenerates a temperature signal representative of the temperatureproximate the thermocouple.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] These and other features of the preferred embodiments of theinvention will become more apparent in the following detaileddescription in which reference is

[0014]FIG. 1 is a perspective view of one embodiment of a small-animalimaging system of the present invention, showing a scanhead assemblymounted onto a first rail and a small-animal mount assembly mounted ontoa second rail.

[0015]FIG. 2 is a perspective view of an alternative embodiment of asmall-animal imaging system of the present invention, showing a scanheadassembly mounted onto a first rail, a small-animal mount assemblymounted onto a second rail, and a needle injection assembly mounted ontoa third rail.

[0016]FIG. 3 is a schematic view of the small-animal imaging system ofFIG. 2.

[0017]FIG. 4 is a side view of the small-animal imaging system of FIG.2.

[0018]FIG. 5 is a perspective view of a first or third rail of thepresent invention.

[0019]FIG. 6 is a perspective view of a movable stop.

[0020]FIG. 7 is an exploded view of the movable stop of FIG. 6.

[0021]FIG. 8 is a perspective view of an embodiment of the second railof the present invention showing two spaced fixed stops.

[0022]FIG. 9 is a perspective view of the scanhead assembly mounted ontothe first rail, showing a mount and a scanhead unit.

[0023]FIG. 10 is a perspective view of a base member of the scanheadassembly showing at least one carriage connected to the bottom of thebase member.

[0024]FIG. 11 is a perspective view of an elongate upright member, acantilever beam, and a scanhead orientation control mechanism of thescanhead assembly of FIG. 9.

[0025]FIG. 12 is an exploded view of the elongate upright member, thecantilever beam, and the scanhead orientation control mechanism shown inFIG. 11.

[0026]FIG. 13 is a perspective view of the small-animal mount assemblymounted onto the second rail.

[0027]FIG. 14 is a perspective view of the small-animal mount assemblyof FIG. 13.

[0028]FIG. 15 is a top view of the small-animal mount assembly of FIG.13.

[0029]FIG. 16 is a side view of the small-animal mount assembly of FIG.13.

[0030]FIG. 17 is a side view of the small-animal mount assembly of FIG.13.

[0031]FIG. 18 is a perspective view of a base member of a mountsubassembly of the small-animal mount assembly shown in FIG. 13.

[0032]FIG. 19 is an exploded view of the base member shown in FIG. 18.

[0033]FIG. 20 is a perspective view of a planar platform of the mountsubassembly.

[0034]FIG. 21 is a perspective view of a portion of a table orientationcontrol mechanism of the mount subassembly.

[0035]FIG. 22 is a perspective view of a housing of an orientationcontrol mechanism of the small-animal mount assembly, showing a portionof the orientation control mechanism.

[0036]FIG. 23 is a perspective view of a housing of an orientationcontrol mechanism of the small-animal mount assembly, showing a portionof the orientation control mechanism.

[0037]FIG. 24 is a perspective view of a housing of an orientationcontrol mechanism of the small-animal mount assembly, showing a portionof the orientation control mechanism.

[0038]FIG. 25 is a top view of the housing of the orientation controlmechanism of FIG. 24.

[0039]FIG. 26 is a perspective view of a portion of the orientationcontrol mechanism.

[0040]FIG. 27 is a perspective view of a portion of the orientationcontrol mechanism.

[0041]FIG. 28 is a perspective view of a portion of the orientationcontrol mechanism showing portions of the housing removed.

[0042]FIG. 29 is a perspective view of a portion of the orientationcontrol mechanism showing portions of the housing removed.

[0043]FIG. 30 is a perspective view of a portion of the orientationcontrol mechanism operatively connected to a table member.

[0044]FIG. 31 is an exploded view of FIG. 6.

[0045]FIG. 32 is a side view of one embodiment of the needle injectionassembly mounted onto the third rail, showing an injector subassemblyand a carriage subassembly.

[0046]FIG. 33 is a perspective view of the needle injection assembly ofFIG. 28.

[0047]FIG. 34 is a perspective view of a rotation adjustment mechanismand a height adjustment mechanism of the carriage subassembly.

[0048]FIG. 35 is an exploded view of the rotation adjustment mechanismand the height adjustment mechanism of FIG. 34.

[0049]FIG. 36 is a perspective view of a first lateral adjustmentmechanism, a second lateral adjustment mechanism, a first tiltadjustment mechanism, and a second tilt adjustment of the carriagesubassembly.

[0050]FIG. 37 is an exploded view of the first lateral adjustmentmechanism, the second lateral adjustment mechanism, the first tiltadjustment mechanism, and the second tilt adjustment mechanism of FIG.36.

[0051]FIG. 38 is a perspective view of a portion of the articulatingarmature subassembly showing the mount member.

[0052]FIG. 39 is a perspective view of a plurality of cooperative armmembers of the articulating armature subassembly.

[0053]FIG. 40 is a partial cross-sectional view of the needle injectionassembly.

[0054]FIG. 41 is a partial cross-sectional view of a portion of theinjector unit.

[0055]FIG. 42 is a perspective view of an injector unit of the injectorsubassembly.

[0056]FIG. 43 is an exploded view of the injector unit of FIG. 42.

DETAILED DESCRIPTION OF THE INVENTION

[0057] The present invention is more particularly described in thefollowing examples that are intended as illustrative only since numerousmodifications and variations therein will be apparent to those skilledin the art. Thus the embodiments of this invention described andillustrated herein are not intended to be exhaustive or to limit theinvention to the precise form disclosed. They are chosen to describe orto best explain the principles of the invention and its application andpractical use to thereby enable others skilled in the art to bestutilize the invention. As used in the specification and in the claims,“a,” “an,” and “the” can mean one or more, depending upon the context inwhich it is used. The preferred embodiment is now described withreference to the figures, in which like numbers indicate like partsthroughout the figures.

[0058] Referring to FIG. 1, one embodiment of an integrated multi-railimaging system 10 of the present invention is shown. The imaging systemincludes a plurality of elongated rails 30, a scanhead assembly 100selectively mounted onto a first rail 32 of the plurality of elongatedrails, and a small-animal mount assembly 200 selectively mounted onto asecond rail 34 of the plurality of elongated rails. In an alternativeembodiment shown in FIGS. 2-4, the imaging system 10 can also include aneedle injection assembly 400 that is selectively mounted onto a thirdrail 36 of the plurality of elongated rails.

[0059] As noted above, and as shown in the figures, the plurality ofelongated rails 30 includes the first rail 32, the second rail 34, and,if the needle injection assembly 400 is used, the third rail 36. Eachrail has a proximal end 35, a spaced distal end 37, and has alongitudinal axis R1, R2, and R3. Each rail 30 can be connected to anelongate support plate 40 by welding or by conventional fasteners, suchas, for example, screws, bolts, or the like. Each support plate can haveat least one damper member 42, such as, for example, rubber feet,connected to and extending from the bottom of the support plates to helpreduce vibrations. The scanhead assembly 100, the small-animal mountassembly 200 and the needle injection assembly 400 each has a basemember 102, 202, 402 that is constructed and arranged for movement in areciprocal or otherwise gliding fashion upon their respective rails in alinear bi-directional manner, i.e., along the respective rail'slongitudinal axis. As one will appreciate, each base member has at leastone carriage 44 connected to the bottom of the base member that isadapted to slide on the respective rail. In one embodiment, each railcan also have a fixed stop 50 connected to the distal end of the rail tolimit the movement of the base member mounted thereto. In an alternativeembodiment, the second rail can have a pair of fixed stops 51 connectedto the second rail and defining two fixed end points for bi-directionaltravel of the base member 202.

[0060] In use, an end edge 46 of the support plate 40 that is connectedto the first rail 32 is connected to a side edge 48′ of the supportplate that is connected to the second rail 34. The proximal end 35 ofthe first rail 32 being positioned adjacent the second rail 34 andbetween the proximal and distal ends 35, 37 of the second rail. In thisconfiguration, the longitudinal axis of the first rail is at an anglewith respect to the longitudinal axis of the second rail. In oneembodiment, the angle γ is about and between 150 to 30 degrees. Inanother embodiment, the angle γ is about and between 130 to 60 degrees.In yet another embodiment, the angle γ is about and between 110 to 70degrees. In another embodiment, the angle γ is about and between 95 to85 degrees.

[0061] If used, an end edge 46 of the base plate 40 that is connectedthe third rail 36 is connected to a side edge 48″ of the base plate ofthe second rail 34 (opposite to the side edge to which the first rail 32is connected). The proximal end 35 of the third rail 36 being positionedadjacent the second rail and between the proximal end and distal end ofthe second rail such that the third rail 36 opposes the first rail 32.In this example, the distal ends of the respective first and third railsextend away from each other and the longitudinal axis of the first andthe third rails are substantially co-axial. Thus, the respectivelongitudinal axis R1, R2, and R3 are fixed in a relative orientationwith respect to one another to provide a common coordinate system.

[0062] The imaging system 10 of the present invention can also includeat least one movable stop 52. Each movable stop 52 is constructed andarranged for movement in a reciprocal or otherwise gliding fashion upontheir respective rails in the linear bi-directional manner, i.e., amongme respective rail's longitudinal axis. In one example, one movable stop52 is mounted to each respective rail intermediate the respective basemember 102, 202, 402 and the proximal end of the rail. In anotherexample, one moveable stop is mounted to each of the first and thirdrails.

[0063] Each movable stop 52 also has a stop clamping mechanism 54 thatcan selectively fix the position of the moveable stop relative to therail member. As one will appreciate, the operator of the system canreadily adjust the position of the movable stops by releasing the stopclamping mechanism, moving the movable stop to the desired position, andclamping the movable stop to the rail at a desired position with thestop clamping mechanism. A portion of the base member 102, 202, 402 canbe selectively and releasable secured to a portion of one respectivemovable stop.

[0064] In one example, the portion of the base member and the portion ofthe movable stop are magnetized with an attractive polarity such that,when brought into proximity to each other, the respective portions ofthe base member and the moveable stop are attracted to each other. Inanother example, a second portion of each base member and a portion ofthe fixed stop are also magnetized with an attractive polarity suchthat, when brought into proximity to each other, the second portion ofthe base member and the portion of the fixed stop are attracted to eachother. Thus, in use, the base members can be selectively moved betweenthe fixed stop and the moveable stop and can be releasably secured tothe movable stop in the desired position. This allows one of the endpoints of travel of the base members to be selectively adjusted andallows the base members to be quickly moved away and brought back to theselected desired position, i.e., back to the selectable end point oftravel.

[0065] Scanhead Assembly

[0066] Referring to the figures, the scanhead assembly 100 includes amount 110 and a scanhead unit 130. The mount 110 includes the basemember 102, an elongate upright member 112, a cantilever beam 114, and ascanhead unit orientation control mechanism 160. The upright member 112is connected to and extends substantially normal to the base member 102(which is mounted as described above to the first rail). The cantileverbeam 114 has a first end 116 and a spaced second end 118. The second end118 of the beam has a sleeve member 120 constructed and arranged formovement in a reciprocal or otherwise gliding fashion upon the exteriorsurface 113 of the upright member 112 in a linear bi-directional manner,i.e., along a longitudinal axis of the upright member. The longitudinalaxis of the beam 114 is co-planar to the longitudinal axis of the firstrail 32.

[0067] The sleeve member 120 of the beam also has a beam lock mechanism122 for selectively mounting the sleeve member at a desired position.For example, in use, a handle 124 of the beam lock mechanism can berotated to loosen the beam lock mechanism, the beam can be raised orlowered into the desired position, and the handle 124 of the beam lockmechanism 122 is rotated to selectively lock the beam into the desiredposition relative to the upright member 122. In one example, theexterior surface 113 of the upright member 112 defines at least onelongitudinally extending groove 115 and the interior surface 121 of thesleeve member 120 has at least one male protrusion 123. The maleprotrusion is sized and shaped for complementary receipt within onegroove 115 of the upright member. In one example, the male protrusion123 extends at least partially along the length of the interior surface121 of the sleeve member.

[0068] In one example, the scanhead unit 130 is an ultrasonic scan head.As one will appreciate however, other scanhead units can be used, suchas, for example, a MRI scanhead, a CT scanhead, and the like. Thescanhead unit 130 is electrically coupled to an external computer 20 forprocessing of the images. The scanhead unit 130 is operatively connectedto the beam 112 of the scanhead assembly 100 in selective orientation bythe scanhead unit orientation control mechanism 160. In one example, thescanhead unit orientation control mechanism comprises an angle controllock mechanism 162 and a ball joint lock mechanism 170. A proximal end164 of the angle control lock mechanism 162 is connected to the beamproximate the first end 116 of the beam. A fixed portion of the anglecontrol lock mechanism extends downwardly away from the beam along asubstantially vertical axis. A distal end 166 of the angle control lockmechanism is connected to a proximal end 172 of the ball joint lockmechanism 170 and is constructed and arranged for pivotal movement ofthe ball joint lock mechanism along an angle control lock plane definedby the coplanar longitudinal axis of the first rail and the beam. As onewill appreciate, the angle control lock mechanism 160 can be movedbetween a locked position and an unlocked position.

[0069] A distal end 174 of the ball joint lock mechanism 170 isconnected to the scanhead unit and is constructed and arranged forpivotal movement of the scanhead unit. As one will appreciate, the balljoint lock mechanism 170 allows the operative end 132 of the scanheadunit to be positioned at an angle with respect to the vertical axis ofthe angle control lock mechanism and with respect to the angle controllock plane. The ball joint lock mechanism 170 is moveable between alocked position and an unlocked position. When the ball joint lockmechanism 170 is locked at the desired angle, it will be appreciatedthat the operative end 132 of the scanhead unit 130 can be moved throughan arc in a desired image plane by selectively unlocking the anglecontrol lock mechanism 160 and moving the angle control lock mechanismalong its fixed range of movement.

[0070] Small-Animal Mount Assembly

[0071] The small-animal mount assembly 200 of the present inventionincludes a table subassembly 210 and a mount subassembly 260. The tablesubassembly 210 includes a table member 212. The mount subassembly 260includes the base member 202, which is mounted to the second rail 34 asdescribed above, a planer platform 262, and a table orientation controlmechanism 280 selectively positioned onto a portion of an upper surface264 of the platform 262. The table orientation control mechanism 280 isconstructed and arranged for adjusting the height, tilt and rotation ofthe operatively connected table member 212 relative to the upper surface264 of the platform 262.

[0072] In one example, an operator selectable plunger lock mechanism 206is connected to the edge of the base member 202. A portion of theplunger lock mechanism is constructed and arranged for selectivelyengaging a portion of a fixed stop 51 connected to the second rail. Theplunger lock mechanism can include a spring mechanism for “locking” theplunger lock mechanism to the respective fixed stop until operator forceis applied to the plunger lock mechanism 206. In use, the operator drawsthe plunger lock mechanism upward to separate the plunger lock mechanismfrom the respective fixed stop. The base member 202 can then be movedalong the longitudinal axis of the second rail until it is selectivelylock to the other fixed stop. In this example, one fixed stop 51 ispositioned proximate the distal end of the second rail and the otherfixed stop 51 is positioned intermediate the proximal and distal ends ofthe second rail.

[0073] In one example, the platform 262 is movably connected to the basemember 202 by a platform adjustment mechanism 270. The platform 262 hasa lower surface 266 that is opposed to the upper surface and defines afirst axis A1 parallel to the longitudinal axis of the second rail and asecond axis A2 normal to first axis. The platform can also have a raisededge 268 extending substantially about the periphery of the platform tohelp prevent the orientation control mechanism from falling from theupper surface 264 of the platform.

[0074] The platform adjustment mechanism 270 is constructed and arrangedfor moving the platform in a platform plane defined by the respectivefirst-axis and second-axis of the platform. A platform base 272 of theplatform adjustment mechanism is connected to a portion of the topsurface 204 of the base member and an adjustable armature 274 of theplatform adjustment mechanism is connected to a portion of an edge ofthe platform 262. In use, rotational movement of a first control knob276 of the platform adjustment mechanism moves the platformbi-directionally relative to the base member along the first axis of theplatform. In the same manner, rotational movement of a second controlknob 278 of the platform adjustment mechanism moves the platformbi-directionally relative to the base member along the second axis ofthe platform. As one will appreciate movement of the platform 262relative to the base member forward or rearward along the respectivefirst or second axis depends upon the direction the first or secondcontrol knob is moved. In one embodiment, the platform can be movedrelative to the base member 202 between end points along each of itsrespective first and second axis less than and including about 100 mm.In another embodiment, less than and including about 80 mm. In yetanother embodiment, less than and including about 60 mm. In anotherembodiment, less than and including about 50 mm.

[0075] In this example, the lower surface 266 of the platform can reston the top surface 204 of the base member 202. Further, the upper andlower surfaces 264, 266 of the platform and the top surface 204 of thebase member are positioned in parallel planes. A coating or sheet oflow-friction material such as, for example, Teflon™ can cover the lowersurface 266 of the platform or the top surface 204 of the base member202. One skilled in the art will appreciate that other low-frictionmaterials are contemplated. Thus, in use, the platform can beselectively moved in the first and second axis within the platform planeunder the control of the platform adjustment mechanism 270. Thelow-friction coating allows this motion to take place with minimalfriction.

[0076] The orientation control mechanism 280 includes a housing 282having a top 284 and a bottom 286. In use, the bottom of the housing isdisposed onto and can be selectively slid along the upper surface 264 ofthe platform 262. The upper surface of the platform can also be coatedwith low-friction material. This low-friction coating allows theoperator to readily position the housing 282 of the orientation controlmechanism onto a desired portion of the upper surface of the platform.The orientation control mechanism includes a magnetic lock 600 that ishoused within the housing. Upon movement of a magnet control knob 602,which extends beyond the exterior of the housing, the magnetic lock 600is movable from a retracted, non-engaged position, to an engagedposition in which a magnet 604 is brought into attractive contact withthe upper surface of the platform. As one will appreciate, when themagnetic lock is in the engaged position, the housing of the orientationcontrol mechanism is fixed relative to the platform due to theattraction of the magnet and the platform. However, even if the magneticlock 600 is in the engaged position, the housing can slide on the uppersurface of the platform if sufficient force is exerted onto the housingor the connected table assembly.

[0077] The orientation control mechanism 280 further can comprise acoarse height mechanism 290, a rotation control mechanism 310, a fineheight control mechanism 320, a first tilt control mechanism 330, and asecond tilt control mechanism 340. The coarse height mechanism is housedwithin the housing and is constructed and arranged for selectivebi-directional movement of an upright shaft member 300 along an uprightaxis of the orientation control mechanism 280. The upright axis issubstantially normal to the longitudinal axis of the second rail 34.Thus, upon movement of a lever control 290 of the coarse heightmechanism, the shaft member 300 can be raised or lowered as desiredbetween a top, extended, position and a lowered, contracted, position.To accommodate the movement of the lever control, the housing defines an“L” shaped slot 294 in one side having an upright portion 296 and alongitudinally extending portion 298 proximate the top of the housing.In the lowered position, the lever control is in lower portion of theupright portion of the slot. In order to raise the top 301 of the shaftmember 300 to its top position, the lever control 292 is lifted upwardthe extent of the upright portion of the slot 294 and is then slid intoand seated within the longitudinally extending portion of the slot.

[0078] The shaft member 300 of the orientation control mechanism can berotated about the upright axis about a bearing 312 positioned within thehousing 282. The rotation brake mechanism 310 is housed within thehousing and is constructed and arranged for selectively engaging a brakesurface 314 connected to the shaft member so that the shaft member canbe fixed in a desired position about the upright axis. Thus, the shaftmember can be rotated by applying a rotational force to the shaft suchthat the table member, which is operatively engaged to the shaft member,can be rotated about the upright axis until the table member is in thedesired orientation. When the shaft member is positioned in the desiredposition, a brake knob 314, which extends beyond the exterior of thehousing, of the rotation brake mechanism 310 can be selectivelyactivated to selectively fix the shaft member in the desired positionrelative to the upright axis.

[0079] A movable cap 322 is operatively connected to the shaft memberand can be selectively moved by the fine height control mechanism 320.The fine height control mechanism is constructed and arranged forselective bi-directional movement of the moveable cap relative to thetop 301 of the shaft member 300 along the upright axis of theorientation control mechanism 280. Thus, upon movement of a heightcontrol knob 324 of the fine height mechanism, the cap 322 can be raisedor lowered as desired. In one embodiment, the cap 322 can be movedrelative to the top 301 of the shaft member between end points along theupright axis less than and including about 50 mm. In another embodiment,less than and including about 30 mm. In yet another embodiment, lessthan and including about 20 mm. In another embodiment, less than andincluding about 10 mm.

[0080] The table member 212 defines a table plane that further definesan x-axis and an y-axis. One will appreciate that the x and y axis ofthe table plane form a common coordinate system. The first tilt controlmechanism 330 is operatively connected to the cap 322 and is constructedand arranged for selectively adjusting and securing the tilt of thetable member 212 relative to the y-axis of the table plane. The secondtilt control mechanism 340 is operatively connected to a bottom surface213 of the table member 212 and is constructed and arranged forselectively adjusting and securing the tilt of the table member relativeto the x-axis of the table plane. A portion of the second tilt controlmechanism 340 is mounted onto a top surface 332 of the first tiltcontrol mechanism 330.

[0081] In this configuration, the first and the second tilt controlmechanisms 330, 340 allow the table member 212 to be angled with respectto the respective y-axis and x-axis of the table plane. In oneembodiment, the angle is less than and including about 60 degrees (i.e.,+/−30 degrees). In another embodiment, the angle is less than andincluding about 45 degrees (i.e., +/−22.5 degrees). In yet anotherembodiment, the angle is less than and including about 30 degrees (i.e.,+/−15 degrees). Thus, in operation, selective manipulation of thecontrols of the mount subassembly 260 by the operator allows the tablemember 212 to be oriented in a desired table surface plane.

[0082] The table member 212 has a top surface 214 that is disposed inthe table surface plane. The table subassembly 210 can also comprise aplurality of ECG electrode contact pads 220, at least one grid ofelectronic heating elements 230, and/or at least one thermocouple 240.In one example, the plurality of ECG contact pads is operativelyattached to the top surface 214 of the table member. Each ECG contactpad senses an ECG signal within a portion of a small animal that issecured against the ECG contact pad. Each ECG contact pad 220 is spacedfrom an adjacent contact pad and can be positioned so that each one ofthe feet/paws of the small animal can be selectively positioned againstone of the ECG contact pads. In one example, the plurality of ECGcontact pads comprises four ECG contact pads that are positioned in aspaced “X” configuration so that the respective feet of the small animalcan be positioned in a splayed position. Each ECG contact pad 220generates an ECG signal 222 representative of the sensed ECG. The ECGsignal can be transmitted through an A/D converter (not shown) to acontrol apparatus 250 on ECG signal line 224. This ECG signal can betransmitted through an isolated ECG amplifier and digital or analoganti-aliasing filter (not shown) to remove noise and amplify the signalbefore processing.

[0083] The grid of electronic heating elements 230 is disposed onto thetop surface 214 of the table member 212 and is electrically coupled tothe control apparatus 250. The temperature of the top surface 214 of thetable member can be adjusted via the control apparatus so that a smallanimal's temperature can be maintained within a desired range when thesmall animal is positioned onto the top surface 214 of the table member.If used, the thermocouple 240 is connected to the top surface of thetable member and can be positioned such that a portion of the smallanimal overlies the thermocouple when the small animal is secured to thetop surface 214. In one example, the thermocouple is positioned near thecenter of the top surface 214 of the table member 212 and is spaced fromthe at least one grid of electronic heating elements 230. Thethermocouple 240 generates a temperature signal 242 representative ofthe sensed temperature of the small animal proximate the thermocouple.The temperature signal 242 can be transmitted through an A/D converter(not shown) to the control apparatus 250 on temperature signal line 244.This temperature signal can be transmitted through an isolated amplifierand digital or analog anti-aliasing filter (not shown) to remove noiseand amplify the signal before processing.

[0084] The table subassembly 210 can also include a rectal temperatureprobe 246. The rectal temperature probe generates an internaltemperature signal 248 representative of the sensed internal temperatureof the small animal with the rectum of the small animal thethermocouple. The internal temperature signal 248 can be transmittedthrough an A/D converter (not shown) to the control apparatus ontemperature signal line 249. This internal temperature signal can betransmitted through an isolated amplifier and digital or analoganti-aliasing filter (not shown) to remove noise and amplify the signalbefore processing.

[0085] In one example, if external embryonic imaging is desired, thetable subassembly 210 can include a walled dish 360 and a dish supportmechanism 370. The dish 360 has a peripheral wall 362 and defines anopening 364 in the bottom of the dish. The dish is formed of asubstantially rigid material, such as, for example, a rigid plastic. Apliable membrane 366 defining a slit 368 is connected to the opening toform a moisture proof connection. In one example, in a relaxed position,the slit in the membrane is closed and is moisture proof. In a stretchedposition, the slit in the membrane is open. The pliable membrane can bea rubber membrane. In another example, the slit 368 in the membrane 366is open in both the relaxed and stretched positions.

[0086] The dish 360 can be selectively held in position relative to thetop surface 214 of the table member 212 by selective actuation of a dishsupport mechanism 370. The dish support mechanism has an arm member 372and a fastener 374. The arm member has an upper portion 376 that isconstructed and arranged for selectively clamping onto a portion of thewall 262 of the dish. As one will appreciate, the dish 260 can beremoved by removing knurled screw 378. The arm member 372 has a lowerportion defining an elongate slot 379. The fastener 374 passes throughthe slot 379 and can selectively secure the lower portion of the armmember to an edge of the table member. In use, the position of anattached dish can be adjusted by loosening the fastener 374, adjustingthe dish 360 into the desired position, and tightening the fastener 374to secure the dish 260 in the desired position.

[0087] In certain externalized procedures, the small animal is securedto the top surface 214 of the table member and the dish 260 is disposedonto the small animal such that the pliable membrane 366 is in thestretched open position with the “open” slit forming a moisture proofseal between the small animal and the dish. In this example, embryos canbe passed through the slit in the rubber membranes and can be imaged inthe dish while still attached to the small animal.

[0088] The table subassembly 210 can also include a clamp member 380secured to a portion of the top surface 214 of the table member. In oneexample, the clamp member 380 is constructed and arranged for grasping aportion of a conical small animal mask 382 that is shaped and sized forfit with the snout of the small animal. The mask 382 is connected to atleast one anaesthetic line that is coupled to an external anaestheticsource, not shown. In an alternative example, the clamp member 380 canselectively grasp a portion of the at least one anaesthetic line.

[0089] Needle Injection Assembly

[0090] Referring now to FIGS. 32-43, one embodiment of the needleinjection assembly 400 is shown. The needle injection assembly isconstructed and arranged for operator control of a needle's insertionpoint, insertion depth, and angle of penetration. The needle injectionassembly 400 further can be constructed and arranged for controlling aneedle plunger 433 of the needle 432.

[0091] In one example, the needle injection assembly 400 includes thebase member 402 (which is connected to the third rail 36 as describedabove), an injector subassembly 420, and a carriage subassembly 450. Theinjector subassembly 420 includes an injector unit 430 that has anelongated needle 432 operatively mounted therein. The needle 432 has alongitudinal length and a distal end 434. The carriage subassembly 450is connected to the base member 402 and provides controls for settingthe needle's insertion point in the small animal in a desired plane,which is typically the same plane as the scanhead unit is set up toimage, i.e., the desired image plane. The carriage subassembly 450 alsoprovides controls for pivoting the needle 432 so that the operator canset a desired angle of penetration to the needle's insertion point inthe small animal. The carriage subassembly 450 can include a rotationadjustment mechanism 460, a height adjustment mechanism 470, a firstlateral adjustment mechanism 480, a second lateral adjustment mechanism490, a first tilt adjustment mechanism 500, a second tilt adjustmentmechanism 510, and an articulating armature subassembly 530.

[0092] The rotation adjustment mechanism 460 is constricted and arrangedfor rotating portions of the carriage subassembly mounted thereon aboutan upright axis. In one example, the rotation adjustment mechanismincludes a housing 462 that is connected to the top surface 404 of thebase member 402. The rotation adjustment mechanism 460 further includesa conventional bearing 464 mounted within the housing that connects toand supports a frame member 465. The frame member 465 has a base 467that is operatively connected to the bearing of the rotation adjustmentmechanism. As one will appreciate, the frame member 465 can rotate aboutan upright axis extending normal to the longitudinal axis of the thirdrail and through the center of the bearing. The rotation adjustmentmechanism 460 can include a rotation lock knob 466 for selectivelylocking the rotation of the frame member so that the amount of rotationof the frame member about the upright axis is limited. The rotationadjustment mechanism can also include a fine rotation adjustment controlknob 468 that allows the operator to rotate the frame member through alimited angle about the upright axis after the rotation lock knob hasbeen engaged. In one embodiment the limited angle is about and between10 degrees (+/−5 degrees). In another embodiment, the angle is about andbetween 8 degrees (+/−4 degrees). In yet another embodiment, the angleis about and between 6 degrees (+/−3 degrees).

[0093] The height adjustment mechanism 470 is operatively connected tothe frame member 465 and is constructed and arranged for raisingportions of the carriage subassembly supported thereon along an uprightaxis. The height adjustment mechanism includes a platform 472 that canbe selectively moved along an upright axis parallel to the upright axisof the rotation adjustment mechanism 460 between a top fixed end pointand a bottom fixed end point. In use, rotation of the height adjustmentknob 474 of the height adjustment mechanism moves the platform of theheight adjustment mechanism bi-directionally relative to the base 467 ofthe frame member along the upright axis. As one will appreciate,movement of the platform 472 upward or downward along the upright axisdepends upon the direction the height adjustment knob 474 is moved. Inone embodiment, the platform 474 of the height adjustment mechanism canbe moved about a center point between fixed end points about and between+/−25 mm. In another embodiment, about and between +/−18 degrees. Inanother example, about and between +/−13 degrees.

[0094] The first lateral adjustment mechanism 480 is connected to and ismounted onto the top surface 476 of the platform 472. The second lateraladjustment mechanism 490 is connected to and mounts thereon aselectively movable top surface 482 of the first lateral adjustmentmechanism 480. The first tilt adjustment mechanism 500 is connected toand mounts thereon a selectively movable top surface 492 of the secondlateral adjustment mechanism 490. Similarly, the second tilt adjustmentmechanism 510 is connected to and is mounted onto a selectively movabletop surface 502 of the first tilt adjustment mechanism 500. Thearticulating armature subassembly 520 is operatively connected to aselectively movable top surface 512 of the second tilt adjustmentmechanism 510.

[0095] The first lateral adjustment mechanism 480 is constructed andarranged for moving the top surface 482 of the first lateral adjustmentmechanism relative to the platform 472 and parallel to an x-axis definedby the platform. This allows the top surface 482 of the first lateraladjustment mechanism 480 to shift toward or away from the proximal endof the third rail 36. In use, rotation of a first lateral adjustmentknob 484 moves the top surface 482 of the first lateral adjustmentmechanism 480 bi-directionally relative to the platform. Similarly, thesecond lateral adjustment mechanism 490 is constructed and arranged formoving the top surface 492 of the second lateral adjustment mechanismrelative to the top surface 482 of the first lateral adjustmentmechanism 480 and parallel to a y-axis defined by the platform (which isnormal to the defined x-axis). This allows the top surface 492 of thesecond lateral adjustment mechanism to shift toward or away from therespective side edges of the third rail 36. In use, rotation of a secondlateral adjustment knob 494 moves the top surface 492 of the secondlateral adjustment mechanism bi-directionally relative to the topsurface 482 of the first lateral adjustment mechanism. As one willappreciate, in another example, the second lateral adjustment mechanism490 can be connected to and mounted onto the top surface 476 of theplatform 472 and the first lateral adjustment mechanism 480 can then beconnected to and mounted thereon the selectively movable top surface 492of the second lateral adjustment mechanism 490.

[0096] The articulating armature subassembly 520 has a mount member 522that is, in one example, connected to the top surface 512 of the secondtilt adjustment mechanism 510. The mount member 522 of the articulatingarmature subassembly defines a mount plane that further defines anx-axis and a y-axis. One will appreciate that the x and y axis of themount plane form a common coordinate system. In one example, the firsttilt adjustment mechanism 500 is operatively connected to the topsurface 492 of the second lateral adjustment mechanism 490 and isconstructed and arranged for selectively adjusting and securing the tiltof the mount member 522 relative to and about the y-axis of the mountmember. The second tilt adjustment mechanism 510 is operativelyconnected to the top surface 502 of the first tilt mechanism 500 and isconstructed and arranged for selectively adjusting and securing the tiltof the mount member 522 relative to the x-axis of the mount member.

[0097] In this configuration, the first and the second tilt adjustmentmechanisms 500, 510 allow the mount member 522 to be angled with respectto the respective y-axis and x-axis of the mount member. In oneembodiment, the angle is less than and including about 40 degrees (i.e.,+/−20 degrees). In another embodiment, the angle is less than andincluding about 20 degrees (i.e., +/−10 degrees). In yet anotherembodiment, the angle is less than and including about 10 degrees (i.e.,+/−5 degrees).

[0098] One will appreciate that, in another example, the second tiltadjustment mechanism 510 can be connected to and mounted thereon aselectively movable top surface of the uppermost of the first or secondlateral adjustment mechanisms. In this example, the first tiltadjustment mechanism 500 is connected to and is mounted onto theselectively movable top surface 512 of the second tilt adjustmentmechanism 510. The mount member of the articulating armature subassembly520 would be operatively connected to the selectively movable topsurface 502 of the first tilt adjustment mechanism.

[0099] The articulating armature assembly 520 includes a plurality ofcooperative arm members 530 that are operatively connected to the mountmember and can be moved by selective actuation of an armature controlmechanism 524. As one will appreciate, selective manipulation of therotation adjustment mechanism 460, the height adjustment mechanism 470,the first lateral adjustment mechanism 480, the second lateraladjustment mechanism 490, the first tilt adjustment mechanism 500,and/or the second tilt adjustment mechanism 510 allows the mount member522 of the articulating armature assembly to be positioned into adesired mount plane defined by a plane extending through the mountmember. The injector unit 430 of the injector subassembly 420 isoperatively mounted within a seat 532 positioned at a distal portion 534of the plurality of cooperative arm members such that the distal end 434of the needle 432 extends beyond the plurality of cooperative armmembers. As one will appreciate, the injector unit 430 is positioned ina needle plane that is normal to the mount plane of the mount member522.

[0100] The articulating armature assembly 520 is constructed andarranged for rotating the injector unit 430 about the distal end 434 ofthe needle in a desired needle plane that is normal to the desired mountplane. In operation, the desired needle plane is substantially coplanarto the desired image plane. As an armature control knob 526 isselectively rotated, the injector unit is between a first fixed endpoint in which the needle 432 is angled at a lower angle of penetrationθ relative to an upright axis to a second fixed end point in which theneedle is angled at a higher angle of penetration θ relative to theupright axis. Thus, the operator can selective set the exact insertionpoint of the needle and, via manipulation of the control of thearticulating armature assembly, can select, within the desired needleplane, a desired angle of penetration θ of the needle into the subjectsmall animal. The articulating armature assembly 520 also includes aposition brake mechanism 540 that can be selectively engaged to fix theplurality of cooperative arm members is a desired position. By “fixing”the plurality of cooperative arm members is the desired position, theoperator can “fix” the desired angle of penetration θ of the needle. Bytightening knob 542 onto a portion of the mount member, the plurality ofcooperative arm members can be selectively “locked” into position.

[0101] The injector subassembly 420 includes the injector unit 430mounted thereon the seat 532 of the articulating armature assembly. Inone example, the injector unit 430 includes a plunger 433, a barrel 436,and the elongate needle 432. The plunger 433 is movable within a definedchamber 437 of the barrel 436. A bore of the needle 432 is incommunication with the chamber of the barrel. In use, the plunger 433can by manually moved in a conventional manner to inject a desiredamount of material into the subject small animal or to draw materialthereinto the chamber of the barrel. In another example, the injectorunit 430 also includes a conventional actuator 440 that is operativelycoupled to the plunger 433. In this example, the actuator 440 is alsoelectrically coupled to a plunger control unit 442. The user can actuatecontrols on the plunger control unit 442 to retract or extend theplunger of the injector unit a desired amount.

[0102] The injector subassembly further comprises a needle insertionmechanism 540 constructed and arranged for controlling the extension andthe retraction of the injector unit 430 relative to the seat 532 of theplurality of cooperative arm members 530. In use, rotation of a needleinsertion control knob 542 of the needle insertion mechanism moves theinjector unit 430, and the attached needle, bi-directionally along theseat and along longitudinal axis of the needle 432. As one willappreciate, insertion or retraction movement of the injector unit andthe attached needle depends upon the direction the needle insertioncontrol knob 542 is moved.

[0103] It will be appreciated that the combination of the releasablecoupling between the movable/fixed stops and the base members of therespective assemblies and the respective rails allows for repositioningof the assemblies while maintaining alignment and relative positioningof the various components. The assemblies can be set up and aligned intheir respective procedure positions and subsequently moved out ofposition to, for example, replace the small animal on the table member.The assemblies can then be returned to their procedure positions to andbe aligned in the same manner as for the previous small-animal on thetable member. In this manner, it will be recognized that the potentiallytime-consuming process of re-aligning the assemblies can be avoided.

[0104] Once the small-animal on the table member is imaged (andinjected), a second small-animal can easily be introduced into the fieldof view with minimal adjustment to either the scanhead unit or, if used,the injector unit, by using the movable/fixed stops, since thesmall-animal mount assembly can slide out of the image plane on its ownrail.

[0105] The imaging system 10 can also include the computer 20 having asystem processor 22. The processor 22 can be coupled to a display ormonitor 24 and to a user input device 26, such as a keyboard, mouse, orother suitable device. If the monitor 24 is touch sensitive, then themonitor 24 itself can be employed as the user input device 26. Acomputer readable storage medium 28 is coupled to the processor. As onewill appreciate, the operation of the scanhead assembly 100, tablesubassembly 210 of the small-animal mount assembly 200, and, if used,the needle injection assembly 400 could be controlled by the computer20. As one skilled in the art will appreciate, the computer readablemedium 28 can include hardware and/or software such as, by way ofexample only, magnetic disks, magnetic tape, optically readable mediumsuch as CD ROM's, and semi-conductor memory such as PCMCIA cards. Ineach example, the medium 28 can take the form of a portable item such asa small disk, floppy diskette, cassette, or it can take the form of arelatively large or immobile item such as hard disk drive, solid statememory card, or RAM coupled to the processor 22. It should be noted thatthe above listed example mediums 28 can be used either alone or incombination. The display 24 could be multipurpose and also serve as ascreen for the imaging system 10. Alternatively, the imaging system canhave a separate screen.

[0106] Operation of the system begins by placing and securing the smallanimal onto the table member such that the small animal's paws areplaced against the ECG pads. The rectal probe is inserted into thesmall-animal and the health parameters are monitored on the controlapparatus 250 and/or the computer 20 throughout the imaging session. Therespective controls of the mount subassembly of the small-animal mountassembly are selectively manipulated to place the table member in thedesired table surface plane. In one example, the small-animal mountassembly can be moved on the second rail until the plunger lockmechanism 206 engages a portion of the fixed stop 51 positionedintermediate the proximal and distal ends on the second rail.Alternatively, the small-animal mount assembly can be moved until aportion of the base member contacts a portion of a previously setmovable stop on the second rail. In this position, the table member ofthe small-animal mount assembly is in the imaging field of the scanheadunit.

[0107] Next, the mount of the scanhead assembly is positioned into aproximate procedure position on the first rail. In one example, themovable stop 50 is slid along and then secured onto the first rail at adesired procedure position that is within a few centimetres of thedesired final procedure position of the mount. One will appreciate thatfine adjustment to the position of the scanhead unit can be made throughmanipulation of the controls of the mount of the scanhead assembly. Themount of the scanhead assembly is moved into contact with the movablestop so that the desired image plane of the scanhead unit is positionedsuch that the image plane bisects the portion of interest in thesmall-animal.

[0108] As one will appreciate, when the imaging session is complete, thesmall-animal mount assembly and the imaging assembly can be moved awayfrom the procedure positions on the first and second rails (toward therespective distal ends of the rails) while maintaining alignment andrelative position of the small-animal mount assembly and the imagingassembly. Thus, the set image plane and the table surface plane will notchange. A new small-animal can be positioned on the table member and thesmall-animal assembly and imaging assembly can be repositioned byrelying upon the previous setting of the movable and/or fixed stops.

[0109] If the needle injection assembly is used, the injector unit isfilled with the fluid to be injected. Next, the base member of theneedle injection assembly is positioned into a proximate procedureposition on the third rail. In one example, the movable stop is slidalong and then secured onto the third rail at a desired procedureposition that is within a few centimetres of the desired final procedureposition of the base member. One will appreciate that fine adjustment tothe position of the needle of the injection unit can be made throughmanipulation of the controls of the carriage subassembly. The basemember of the needle injection assembly is moved into contact with themovable stop and the controls of the carriage subassembly aremanipulated so that the needle can be placed in the desired needleplane, which can also be the set image plane of the scanhead unit. Thecarriage subassembly can also be manipulated to select the desired angleof penetration of the needle within the desired needle plane.

[0110] The needle is advanced into the subject small-animal at theneedle's insertion point to a desired depth and the sample material isinjected either manually or by using the plunge control unit. Typically,confirmation of injected material, such as fluid, can often be seen onthe screen of the system as the tissue surrounding the distal end of theneedle accommodates the extra volume. The needle can then be withdrawnand the procedure is complete.

[0111] Subsequently, the needle injection assembly, the scanheadassembly, and/or the small-animal mount assembly can be selectivelymoved away from their procedure positions. A new animal can bepositioned onto the table member of the small-animal mount assembly andthe needle injection assembly, the scanhead assembly, and/or thesmall-animal mount assembly can be repositioned by relying upon theprevious settings of the movable/fixed stops. One will appreciate thatthe planes of the scanhead unit and the injector unit will remainco-planer.

[0112] It is contemplated that many other procedures can be done usingthe imaging system 10 of the present invention. The multi-rail design ofthe imaging system enables an operator to precisely align the needle ofthe needle injection assembly within the imaging plane of the scanheadunit of the scanhead assembly. The needle injection assembly, thesmall-animal mount assembly, and the scanhead assembly can then be movedback and forth along their respective rails 32, 34, 36 and be broughtback to their original procedure positions without losing the alignmentof the image plane or the co-planer alignment between the needle of theinjector unit and the image plane of the scanhead unit.

[0113] It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present inventionwithout departing from the scope or spirit of the invention. Otherembodiments of the invention will be apparent to those skilled in theart from consideration of the specification and practice of theinvention disclosed herein. It is intended that the specification andexamples be considered as exemplary only, with a true scope and spiritof the invention being indicated by the following claims.

What is claimed is:
 1. A small-animal mount assembly for mounting asmall animal, comprising: a control apparatus; a table member having atop surface, a bottom surface, and defining a table plane; and at leastone ECG control pad, the at least one ECG control pad attached to thetop surface of the table member and electrically coupled to the controlapparatus, each ECG pad generating an ECG signal representative of asensed ECG of a portion of the small animal disposed thereon the ECGpad.
 2. The small-animal mount assembly of claim 1, further comprisingat least one grid of electronic heating elements disposed onto the topsurface of the table member.
 3. The small-animal mount assembly of claim2, wherein the at least one grid of electronic heating element iselectrically coupled to the control apparatus.
 4. The small-animal mountassembly of claim 2, further comprising a thermocouple connected to thetop surface of the table member and electrically coupled to the controlapparatus, the thermocouple generating a temperature signalrepresentative of the temperature proximate the thermocouple.
 5. Thesmall-animal mount assembly of claim 4, further comprising a rectaltemperature probe that is electrically coupled to the control apparatus,the rectal temperature probe generating an internal temperature signalrepresentative of the sensed internal temperature of the small animal.6. The small-animal mount assembly of claim 1, further comprising: adish having a peripheral wall; a dish support mechanism having an armmember and a fastener, the arm member having an upper portion and alower portion, the upper portion of the arm use, the fastener passesthrough the slot and selectively secures a portion of the lower portionof the arm member to an edge of the table member.
 7. The small-animalmount assembly of claim 1, further comprising: a small animal maskshaped and sized for fit onto a portion of the snout of the smallanimal; and a clamp member secured to a portion of the top surface ofthe table member, the clamp member constructed and arranged for graspinga portion of the small animal mask.
 8. The small-animal mount assemblyof claim 1, further comprising means for orienting the table member sothat the table plane of the table is positioned in a desired tableplane.
 9. The small-animal mount assembly of claim 8, wherein the meansfor orienting the table member includes an orientation controlmechanism.
 10. The small-animal mount assembly of claim 9, wherein theorientation control mechanism includes: a movable cap having a top; afirst tilt control mechanism having a top surface, the first tiltcontrol mechanism operatively connected to the top of the movable cap;and a second tilt control mechanism having a portion operativelyconnected to the top surface of the first tilt control mechanism and aportion operatively connected to the bottom surface of the table member;wherein the first tilt control mechanism is constructed and arranged forselectively adjusting and securing the tilt of the table member relativeto the y-axis of the table plane, and wherein the second tilt controlmechanism is constructed and arranged for selectively adjusting andsecuring the tilt of the table member relative to the x-axis of thetable plane.
 11. The small-animal mount assembly of claim 10, whereinthe orientation control mechanism includes: a shaft member having anupper portion and a top, the movable cap being movably engaged with theupper portion of the shaft member; and a fine height control mechanismconstructed and arranged for selective bi-directional movement of themovable cap relative to a top of the shaft member along an upright axis.12. The imaging system of claim 11, wherein the orientation controlmechanism includes: a housing; a bearing housed within the housing, theupright shaft member being operatively engaged with the bearing suchthat the shaft member can be selectively rotated about the upright axis;and a coarse height mechanism constructed and arranged for selectivebi-directional movement of the upright shaft member along the uprightaxis.
 13. The imaging system of claim 13, wherein the orientationcontrol mechanism includes: a brake surface connected to the shaftmember; and a rotation control mechanism constructed and arranged forselectively engaging the brake surface.
 14. A small-animal mountassembly for mounting a small animal, comprising: a control apparatus; atable member having a top surface, a bottom surface, and defining atable plane; and at least one grid of electronic heating elementsdisposed onto the top surface of the table member.
 15. The small-animalmount assembly of claim 14, wherein the at least one grid of electronicheating element is electrically coupled to the control apparatus. 16.The small-animal mount assembly of claim 14, further comprising at leastone ECG control pad, the at least one ECG control pad attached to thetop surface of the table member and electrically coupled to the controlapparatus, each ECG pad generating an ECG signal representative of asensed ECG of a portion of the small animal disposed thereon the ECGpad.
 17. The small-animal mount assembly of claim 14, further comprisinga thermocouple connected to the top surface of the table member andelectrically coupled to the control apparatus, the thermocouplegenerating a temperature signal representative of the temperatureproximate the thermocouple.
 18. The small-animal mount assembly of claim14, further comprising a rectal temperature probe that is electricallycoupled to the control apparatus, the rectal temperature probegenerating an internal temperature signal representative of the sensedinternal temperature of the small animal.
 19. The small-animal mountassembly of claim 14, further comprising: a dish; a dish supportmechanism having an arm member and a fastener, the arm member having anupper portion and a lower portion, the upper portion of the arm memberconstructed and arranged for selectively clamping onto a portion of thedish, the lower portion of the arm member defining an elongate slot,wherein, in use, the fastener passes through the slot and selectivelysecures a portion of the lower portion of the arm member to an edge ofthe table member.
 20. The small-animal mount assembly of claim 14,further comprising means for orienting the table member so that thetable plane of the table is positioned in a desired table plane.
 21. Thesmall-animal mount assembly of claim 20, wherein the means for orientingthe table member includes an orientation control mechanism.
 22. Asmall-animal mount assembly for mounting a small animal, comprising: acontrol apparatus; a table member having a top surface, a bottomsurface, and defining a table plane; means for orienting the tablemember so that the table plane of the table is positioned in a desiredtable plane; at least one grid of electronic heating elements disposedonto the top surface of the table member; and at least one ECG controlpad, the at least one ECG control pad attached to the top surface of thetable member and electrically coupled to the control apparatus, each ECGpad generating an ECG signal representative of a sensed ECG of a portionof the small animal disposed thereon the ECG pad.
 23. The small-animalmount assembly of claim 22, wherein the at least one grid of electronicheating element is electrically coupled to the control apparatus. 24.The small-animal mount assembly of claim 22, further comprising athermocouple connected to the top surface of the table member andelectrically coupled to the control apparatus, the thermocouplegenerating a temperature signal representative of the temperatureproximate the thermocouple.
 25. The small-animal mount assembly of claim22, further comprising a rectal temperature probe that is electricallycoupled to the control apparatus, the rectal temperature probegenerating an internal temperature signal representative of the sensedinternal temperature of the small animal.
 26. The small-animal mountassembly of claim 22, further comprising: a dish having a peripheralwall; a dish support mechanism having an arm member and a fastener, thearm member having an upper portion and a lower portion, the upperportion of the arm member constructed and arranged for selectivelyclamping onto a portion of the wall of the dish, the lower portion ofthe arm member defining an elongate slot, wherein, in use, the fastenerpasses through the slot and selectively secures a portion of the lowerportion of the arm member to an edge of the table member.
 27. Thesmall-animal mount assembly of claim 22, wherein the means for orientingthe table member includes an orientation control mechanism.
 28. Thesmall-animal mount assembly of claim 22, further comprising: a railhaving a proximal end, a spaced distal end, and a longitudinal axis;means for supporting the table member on the rail; and means for movingthe table member in a linear bi-directional manner along thelongitudinal axis of the rail between a first end point and a second endpoint.